1. Field of the Invention
The present invention relates to an image forming apparatus for forming an image on a photoconductive element by an electrophotographic process.
2. Discussion of the Background
Conventional image forming apparatuses include one having exposing devices and developing devices provided in pairs and arranged around a photoconductive element, as disclosed in, for example, Japanese Patent Laid-Open Publication Nos. 19764/1982, 65570/1989, 223475/1989, 148063/1990, and 203315/1990. Each pair of exposing device and developing device is assigned to a particular color.
Each of the exposing devices at least includes a laser unit for emitting a laser beam, a cylindrical lens for condensing the laser beam in the subscanning direction, a polygonal mirror for deflecting the condensed laser beam, a motor for driving the polygonal mirror, an f-theta lens for correcting the laser beam from the polygonal mirror, and optical elements for conducting the corrected laser beam onto the photoconductive element. The problem with such an exposing device is that the optical path is extremely long and the structure is bulky. Moreover, the exposing devices each having the above construction cause a substantial space around the photoconductive element to be simply wasted, making the overall apparatus large sized.